As people look to conserve energy by reducing power consumption, solar energy becomes a viable option to provide power for lighting systems in public areas. However, in some parts of the world, particularly at certain times of the year, the amount of sunlight available to charge a solar-powered system may simply not provide sufficient energy to power a lighting system for an extended period of time at night or in low light conditions. While more energy may be obtained by using larger solar panels, such solution is restricted by space and cost considerations. It is therefore desirable to use a lighting system that conserves as much energy as possible, by selectively activating only when light is required for a user.
The present invention provides selective illumination in the immediate vicinity of a user moving through an open area or along a path by detecting the presence of the user and anticipating the user's progress through the area.
Motion-sensitive lighting is often used in infrequently accessed areas, where continuous lighting may be unnecessary and expensive. For example, it is well known to provide motion sensor-activated lighting in connection with security systems. Such motion-sensitive lighting is often intended as a deterrent and is therefore often very bright and harsh, tending to suddenly flood a particular area with light.
Motion-sensitive lighting may also be intended to assist a user, for example by illuminating an area so that a user may quickly view an area of interest. Such illumination again tends to be relatively sudden and harsh, which can actually hinder a user's efforts, for example, as he seeks a keyhole to unlock a door.
In the context of a person travelling through an open area or along a path, immediate and harsh lighting may be undesirable and may detract from the enjoyment of the stroll and from the mood of the visitor. When used in an area adjacent other occupants or residents, sudden intermittent lighting may also be is viewed as light pollution.
The use of typical prior art motion sensor technology in an open area or along a path would also entail the user who wishes to proceed in a given direction having to commit to an area that is initially unlighted until a motion sensor detects the user and activates a light—a potentially unnerving experience for some.
Prior art motion sensors most often activate their associated lights for a predetermined period of time after motion has been detected, following which the light turns off. This pre-determined persistency fails to take into account the speed and progress of a user along a path, resulting in wasted energy and imprecise tracking of the user.
In an attempt to maximize the responsiveness of lighting systems, it is known to assign to each light in a lighting system a unique identifier enabling each light to be separately instructed and controlled. U.S. Pat. No. 6,292,901 describes such a system in which DIP switches are manually set on each light in a lighting network. This means of configuring a lighting network is obviously labour-intensive, time consuming and prone to human error.
U.S. Patent Publication No. 2007/0057807 discloses a network of luminaire managers. Once the network is configured, each luminaire manager transmits information on the status of a luminaire under its control to a central network server. Each manager also communicates with the neighboring managers upon installation, to ensure that it is operational. Configuration is accomplished by collecting the identification number for each luminaire, its GPS grid coordinates, the type of equipment (such as sensors and lights) installed, and the initial equipment parameters, using a portable field unit operated by the installer. The information must then be downloaded to the central operations system.
U.S. Pat. No. 6,859,644 discloses a networked lighting system wherein each new lighting device requests an identification code from a master control. The master control transmits an identification code to the lighting device, and then requests verification that the code has been received. Once the code has been received and stored, the lighting device provides a visual indication to a user, such as by illuminating. In order to complete the sequence, the user must press a button on a remote control, confirming receipt of the visual indication.
U.S. Patent Publication No. 2004/0160199 describes attaching a programming device to a lighting device, then selecting a mode, such as programming mode or addressing mode. The programming device may transmit the lighting device's pre-programmed identification code to the central controller, or the central controller may transmit an address to the programming device, which deposits the code into the lighting device's memory. The same programming device is apparently attached to each lighting device in turn. Alternatively, the central controller may query a controller on a lighting device, and assign an identification code once it receives a response from the controller.
U.S. Patent Publication No. 2004/0254725 discloses a plurality of lighting devices, each of which may have its own integrated communication and control module. A central controller polls each module, using incremental serial numbers. Once a module receives its own serial number, it responds with its location coordinates. The central controller may then display a map of all lighting device locations. In larger networks, branches of lighting devices can each have their own local controller, and the branches are then networked through a central controller. However, it is desirable to eliminate excess levels of control in a given system, in order to reduce the complexity of the system, as well as the overall cost of implementing it. Further, autonomous operation of the lighting devices in a system is preferred in order to maximize the system responsiveness.
It is an object of the invention to provide an intelligent, user-responsive lighting system to illuminate an area or a path.
It is a further object of the invention to provide lighting for a user of an area that will gradually and progressively illuminate the user's path, and that may gradually and softly extinguish the lights after the user has passed so as to provide a less stressful and more pleasant illumination effect.
It is a further object of the invention to provide pathway lighting that directs the user along the path by anticipating the user's progress and direction.
It is yet a further object of the invention to provide a lighting system that is easily configurable with a minimum of effort on the part of the installer.
It is yet a further object of the invention to provide an intelligent lighting system in which the individual lighting elements and their associated control mechanisms may be quickly and simply installed.
These and other objects of the invention will be appreciated by reference to the summary of the invention and to the detailed description of the preferred embodiment that follow, it being understood that not all objects are necessarily simultaneously attained by each aspect of the invention, and that not all objects are necessarily fulfilled by each claim of the application.